Sandwich structures commonly include a pair of thin and rigid facesheet materials separated by a lightweight reinforcing core. Sandwich structures are widely used as structural components in both advanced aerospace and automotive designs due to their high specific strength and stiffness. Conventionally, the lightweight reinforcing core includes a closed-cell material, such as balsa wood, honeycomb, or closed-cell foam. However, closed-cell cores do not permit fluid to flow through the core. Accordingly, sandwich structures having closed-cell cores are not suitable for applications in which fluid must flow through the core, such as heat exchangers or cold plates.
Sandwich structures having a directionally open core, such as a corrugated core, may be suitable for applications in which fluid must flow through the core. However, sandwich structures having directionally open cores must be sealed to prevent fluid ingress into the core, which may damage or corrode the core, and to prevent fluid egress from the core to the surrounding environment. Conventional methods for sealing a directionally open core, such as applying a potting compound around a periphery of the core, are costly, labor-intensive, and not readily scalable. Additionally, such conventional techniques for sealing a directionally open core are impractical or ineffectual at sealing sandwich structures having a fully open cellular core in which fluid is able to flow in any direction through the core.